Medium large transport is not where the controller expects to be.

Attributes
ACN	120463
Time
Date	198908
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	msl bound lower : 4000 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 210 flight time total : 11000 flight time type : 1600
ASRS Report	120463
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 135 flight time total : 6800 flight time type : 2100
ASRS Report	120475
Events
Anomaly	altitude deviation : overshoot other anomaly other other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

Ord approach cleared us to 6000', when level at 6000' controller asked us why we were at 6000'. We responded that we were cleared to 6000' (as we had previously read back to him), then we were cleared to 4000'. Next we were assigned a 120 degree heading and given an approach clearance (which we also read back) when we were in the turn to 120 degrees. The controller asked us where we were going, then assigned us a new heading. As a possible contributing factor, there was another aircraft on the same frequency with a similar sounding call sign. There was no conflict with any other aircraft.

Original NASA ASRS Text

Title: MLG IS NOT WHERE THE CTLR EXPECTS TO BE.

Narrative: ORD APCH CLRED US TO 6000', WHEN LEVEL AT 6000' CTLR ASKED US WHY WE WERE AT 6000'. WE RESPONDED THAT WE WERE CLRED TO 6000' (AS WE HAD PREVIOUSLY READ BACK TO HIM), THEN WE WERE CLRED TO 4000'. NEXT WE WERE ASSIGNED A 120 DEG HDG AND GIVEN AN APCH CLRNC (WHICH WE ALSO READ BACK) WHEN WE WERE IN THE TURN TO 120 DEGS. THE CTLR ASKED US WHERE WE WERE GOING, THEN ASSIGNED US A NEW HDG. AS A POSSIBLE CONTRIBUTING FACTOR, THERE WAS ANOTHER ACFT ON THE SAME FREQ WITH A SIMILAR SOUNDING CALL SIGN. THERE WAS NO CONFLICT WITH ANY OTHER ACFT.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.